10 research outputs found
Impact of apical foreshortening on deformation measurements: A report from the EACVI-ASE Strain Standardization Task Force
Aims Foreshortening of apical views is a common problem in
echocardiography. It results in an abnormally thick false apex and a
shortened left ventricular (LV) long axis. We sought to evaluate the
impact of foreshortened (FS) on LV ejection fraction (LVEF) and
layer-specific 2D speckle tracking based segmental (S) and global (G)
longitudinal strain (LS) measurements.
Methods and results We examined 72 participants using a GE Vivid E9
system. FS apical views were collected from an imaging window one
rib-space higher than the optimal images. Ejection fraction as well as
layer-specific GLS and SLS measurements were analysed by GE EchoPAC v201
and TomTec Image Arena 4.6 and compared between optimal and FS images.
On average, LV long axis was 10\% shorter in FS images than in optimal
images. FS induced a relative change in LVEF of 3.3\% and 6.9\% for GE
and TomTec, respectively (both, P < 0.001). Endocardial GLS was 9.0\%
higher with GE and 23.2\% with TomTec (P < 0.001). Midwall GLS
measurements were less affected (7.8\% for GE and 14.1\% for TomTec,
respectively, both P< 0.001). Segmental strain analysis revealed that
the mid-ventricular and apical segments were more affected by
foreshortening, and endocardial measurements were more affected than
midwall.
Conclusion Optimal image geometry is crucial for accurate LV function
assessment. Foreshorhening of apical views has a substantial impact on
longitudinal strain measurements, predominantly in the apex and in the
endocardial layer. Our data suggest that measuring midwall strain might
therefore be the more robust approach for clinical routine use
Toward an Operational Anthropogenic CO2 Emissions Monitoring and Verification Support Capacity
International audienceUnder the Paris Agreement (PA), progress of emission reduction efforts is tracked on the basis of regular updates to national greenhouse gas (GHG) inventories, referred to as bottom-up estimates. However, only top-down atmospheric measurements can provide observation-based evidence of emission trends. Today, there is no internationally agreed, operational capacity to monitor anthropogenic GHG emission trends using atmospheric measurements to complement national bottom-up inventories. The European Commission (EC), the European Space Agency, the European Centre for Medium-Range Weather Forecasts, the European Organisation for the Exploitation of Meteorological Satellites, and international experts are joining forces to develop such an operational capacity for monitoring anthropogenic CO 2 emissions as a new CO 2 service under the EC's Copernicus program. Design studies have been used to translate identified needs into defined requirements and functionalities of this anthropogenic CO 2 emissions Monitoring and Verification Support (CO 2 MVS) capacity. It adopts a holistic view and includes components such as atmospheric spaceborne and in situ measurements, bottom-up CO 2 emission maps, improved modeling of the carbon cycle, an operational data-assimilation system integrating top-down and bottom-up information, and a policy-relevant decision support tool. The CO 2 MVS capacity with operational capabilities by 2026 is expected to visualize regular updates of global CO 2 emissions, likely at 0.05° x 0.05°. This will complement the PA's enhanced transparency framework, providing actionable information on anthropogenic CO 2 emissions that are the main driver of climate change. This information will be available to all stakeholders, including governments and citizens, allowing them to reflect on trends and effectiveness of reduction measures. The new EC gave the green light to pass the CO 2 MVS from exploratory to implementing phase